The first capacitor diode or rectifier voltage multiplying circuit was invented 100 years ago by Heinrich Greinacher. Though it was only a half wave multiplier it was quickly improved to full wave, and has been a circuit standard for increasing voltage without the need for a transformer. It also is often used after a transformer for very high voltages. The primary advantages of this circuitry are smaller components, lower weight, higher voltages and less cost than transformer based solutions. The core approach to these multipliers is serial stacking of capacitors and diodes (a 2× will have single capacitors in series, a 4× will have two capacitors in series, etc.); in a sense, attaining multiplication through addition.
There are many circuits which only require low multiples of full wave input, but with one exception (U.S. Pat. No. 3,292,073, issued Dec. 13, 1966, Jones, R. E. et al.), the full wave multiples are all even numbers. That one exception's primary problem is that it requires more parts than the next higher, even-number, standard multiplier. (It has twice as many capacitors before the final output capacitor, and twice as many diodes or rectifiers for the times three multiplier.) But the Jones multiplier also is less reliable than the bracketing even-multiple circuits. (So each of the 2× and 4× multipliers are more reliable than a Jones 3× multiplier, due to the fewer parts required.) While a Jones odd number voltage multiplier might be usable in some situations, it is generally not a cost competitive product.
This invention overcomes these difficulties by providing a process to produce an odd numbered multiplier with fewer parts than the above-mentioned solution. Like the Jones odd numbered voltage multiplier, the odd-number voltage multiplier produced by the process of the present invention provides theoretically identical impedance to both phases of the alternating current (AC) voltage source, thus minimizing power line disturbances which could have resulted from the different current responses for each phase of the input power.
Also, in cases in which the source of the AC input power is a power bridge, it results in more reliable operation of the circuit; principally through preventing circuit failures such as blown transistors, which occurred as a result of the timing mismatch between the two output phases of the power bridge, primarily due to the different input impedances seen by the bridge's two phases of the standard full wave voltage multiplier.